A268336 a(n) = A174824(n)/n, where A174824(n) = lcm(A002322(n), n) and A002322(n) is the Carmichael lambda function (also known as the reduced totient function or the universal exponent of n).

1, 1, 2, 1, 4, 1, 6, 1, 2, 2, 10, 1, 12, 3, 4, 1, 16, 1, 18, 1, 2, 5, 22, 1, 4, 6, 2, 3, 28, 2, 30, 1, 10, 8, 12, 1, 36, 9, 4, 1, 40, 1, 42, 5, 4, 11, 46, 1, 6, 2, 16, 3, 52, 1, 4, 3, 6, 14, 58, 1, 60, 15, 2, 1, 12, 5, 66, 4, 22, 6, 70, 1, 72, 18, 4, 9, 30, 2, 78, 1, 2

Offset

1,3

Links

Table of n, a(n) for n=1..81.

Formula

a(n) = A174824(n)/n.

a(A124240(n)) = 1. - Michel Marcus, Feb 21 2016

Mathematica

Table[LCM[n, CarmichaelLambda@ n]/n, {n, 100}] (* Michael De Vlieger, Feb 03 2016, after T. D. Noe at A174824 *)

Prog

(Magma) [1] cat [Lcm(n, CarmichaelLambda(n))/n: n in [2..100]]: // Feb 03 2016
(PARI) a(n)=my(ps); ps=factor(n)[, 1]~; m = n; for(k=1, #ps, m=lcm(m, ps[k]-1)); m/n \\ Michel Marcus, Feb 21 2016
(PARI) apply( {A268336(n)=lcm(lcm([p-1|p<-factor(n)[, 1]]), n)/n}, [1..99]) \\ [...] = znstar(n)[2], but 3x faster. - M. F. Hasler, Nov 13 2019

Crossrefs

Cf. A002322, A068563, A124240, A174824.

Sequence in context: A063994 A373318 A374127 * A295127 A076512 A128707

Adjacent sequences: A268333 A268334 A268335 * A268337 A268338 A268339

Keyword

nonn,easy

Author

Juri-Stepan Gerasimov, Feb 01 2016

Extensions

More terms from Vincenzo Librandi, Feb 03 2016

Status

approved